A door and opener from 1987 were built for a moderate heat climate that hasn't changed much, so the failures we see aren't usually weather damage, they're wear. Extension or early torsion springs rated for a certain number of cycles simply run out, and on a door this age that point tends to arrive without much warning. Weatherstripping around the panels has typically hardened and cracked from decades of Texas summers, which lets in more heat and dust than a newer gasket would. When we're out this way, replacing a spring often means also flagging worn rollers or a chain-drive opener that's due, since fixing one part on a thirty-plus-year-old system and ignoring the rest just moves the next call a few months down the road.